Fast And Furious: Four High Intensity Interval Training Workouts Explained

You’d be forgiven for not knowing what High Intensity Interval Training (HIIT) is, except it was ranked #1 World Fitness Trend in 2014 and #2 in 2015, so chances are you have actually heard of it, even if you don’t know exactly what it is.

Some HIIT popularised workouts include Tabata, F45 and CrossFit. Sound familiar?
While it’s not been without controversy – despite what you’ve been heard, HIIT remains one of the most effective ways to burn fat, lose weight and build muscle – F A S T. This has been proven by several very scientific studies, so consider it the highest truth.
Rob Hale, Head of Fitness at Fitness First Australia credits the workout’s cult status to its short and customisable nature. And adds this to boot: “[HIIT] is proven to have some of the best after-burn rates of any training [so] you’ll continue to burn fat even after the workout is finished.”
Still, it’s a lot to get your head around so here’s a wrap-up so you can decide which is best for you particular set of needs…

HIIT: The Original.

What is it? A real werkout involving intervals of high intensity exercise (where your heart rate reaches 80-90% of maximum = optimal for fat burn) followed by short ‘rest’ intervals of low intensity to no exercise. HIIT sessions typically go for 20 to 30 minutes and are done three times a week. It’s not advisable to do more than that because of the toll HIIT takes the body, heart and nervous system.
What is done? HIIT can be applied to any sport from swimming to cycling, but more recently, specialty classes that combine body-weight training (squats, push-ups, sit-ups) and equipment-use (kettlebell, dumbbell, elliptical machine) have made HIIT a more holistic, total body workout.
Challenges? The controversy surrounding HIIT comes from its potential risk for injury when some people over do it or do it incorrectly, as is the case with any sport. Rob recommends starting out in a class, or at least with some professional guidance to avoid wrecking yourself.
Where it’s done? Fitness First offers 30 to 45 minute HIIT classes, FYI.
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TABATA: The Time-Poor Person’s HIIT.

What it is? Tabata is a four-minute workout, involving successive sets of 20 seconds of work followed by 10 seconds of rest (= 8 x 30-second sets). The theory is that because you’re “working” over a shorter period of time, you have the motivation and energy to pump out more reps and are therefore able to reach higher intensities and raise your metabolic rate more quickly.

What is done? Since Tabata is a low-maintenance workout, it uses mainly body weight exercises, like squats, burpees and lunges (anything that relies on your ‘body weight’, hence the name) as well as cardio exercises like sprinting and high-knees. Basically, anything that you can do without equipment.
Challenges? Loneliness :(. Unlike many other popular HIIT workouts, Tabata is DIY. Also, boredom because body weight exercises get old real fast.
Where it’s done? Anywhere, anytime. Tabata apps like Tabata! 4-Minute Daily Workouts ($1.99) and Tabata Trainer ($1.99) function as a self-timer and are pre-loaded with workouts.

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CROSSFIT: HIIT gets serious.

What is it? CrossFit is very much its own entity. With such a large community of dedicated followers, an internationally recognised CrossFit Games, its own WODs (Workout Of The Day) published everyday on the official CrossFit website, it’s a fully-fledged sport. 
CrossFit differs from traditional HIIT in that its workouts tend to be more technical and its programming is more rep-focused. So, instead of being given a specific time (e.g. 20 seconds of work), often in CrossFit you’re just given a specific number of reps (e.g. 20 burpees or 20 lifts) that you have to pump out and your ‘best time’ is recorded. Progress is measured over time through improvement in speed and strength.
What is done? Amelia Thomsett, Head Coach at CrossFit Victoria says CrossFit is so unique because of it’s a mix of disciplines from gymnastics to Olympic and power lifting, to body weight and aerobics exercises and cardio training, just to name a few. Though, CrossFit workouts and training methods do vary from gym to gym.
Challenges?  One of the initial challenges, Amelia says, is learning all the different moves. CrossFitters have their own lingo, but after you’ve done the workout once, it quickly becomes familiar. Also, workouts are totally scalable, so if the WOD prescribes a certain weight to lift, you can start with a lighter weight and work up to the prescribed one.
Where it’s done? CrossFit Victoria is one of many accredited CrossFit gyms popping up around the country; Google to find your nearest for a consultation.
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F45: HIIT as a team sport. 

What is it? F45 is short for functional training, i.e. designed to help you ‘function’ and move better IRL. The sessions are 45 minutes long, and it’s a circuit style workout. F45 returns to the traditional time-based HIIT model, with workouts involving successive intervals of 30-40 second work and 10-20-second rest.
Unlike CrossFit, you’re not working to push out a specified number of reps, but don’t think that means you can slack off. F45 is highly team-oriented, which should keep you motivated enough, but just in case it doesn’t, they strap a heart rate monitor of you. There is no safe place.
What is done? Daniel Conn, Ambassador of F45 Australia and Elite Functional Trainer says it’s the most systemised form of training on the planet. There are 10 stations that change everyday, and you work in small groups rotating from station to station. There are literally 1000s of exercises you can do from machine work to kettle bell lifts, jump rope to body weight moves. The only thing there’s not any of, Daniel says, are Olympic or technical lifts, which makes the sport a bit more approachable and less risk-prone.
Challenges? The obvious. If you’re not a fan of bootcamp-style workouts or sweating it up with others, stay away. But, if you champion solidarity and belief safety in numbers is true, come. Join them.
Where it’s done? Check out the F45 Academy website to find the nearest location near you. 

Cover Image and video via F45 Training